A wide variety of elongated medical instruments are currently available that are adapted to be permanently or temporarily implanted in the mammalian body, usually the body of a human patient, or used to access a site in the body to facilitate introduction of a further implantable medical device or delivery of a therapeutic or diagnostic agent. Such elongated medical instruments have an instrument body extending between instrument body proximal and distal ends, and a distal segment of the instrument body is advanced to a remote site in the body.
In many cases, the introduction of such elongated medical instruments to a remote site in the body is effected through a skin incision accessing an incision into a blood vessel, whereby the instrument body is advanced through a pathway until the distal segment or the instrument body distal end are located at the remote site. Such advancement is often through a tortuous pathway having twists and turns requiring the capability to impart a curve or deflect the instrument body distal end to facilitate advancement. Therefore, the introduction of such elongated medical instruments through vascular pathways or other tortuous pathways in the body is facilitated by a wide variety of techniques and mechanisms that have been developed to impart curves in the distal segment of the instrument body or to deflect or steer the instrument body distal end.
There is still a perceived need for a steerable stylet having a small diameter stylet body that is simple and inexpensive to manufacture, resists kinking, and that can be manipulated to control the deflection of and impart a bend in a distal segment of the stylet body that is more acute.